Control of Asymmetric Cascaded Multilevel Inverters Based on Charge Balance Control Methods

摘要

In this paper, a new algorithm is proposed to determine the magnitudes of dc voltage sources in asymmetric cascaded multilevel inverters. Using this algorithm, it is possible to generate the maximum number of output voltage levels and maximum output voltage amplitude with minimum number of dc voltage sources. Using this algorithm, it is possible to use charge balance control methods to all dc sources except the minimum amplitude dc voltage source (first H-bridge). Therefore, the lifetime of dc voltage sources used in different H-bridges of cascaded asymmetric multilevel inverter except the first H-bridge are the same. As a result, the system's maintenance cost will be low. The simulation and experimental results confirm the abilities of the proposed method.